Photochromic Polymers

The chief methods of preparation and the photochromic properties of polymers containing covalently bound photochromic groups in the main or a side chain of the macromolecule are surveyed. The properties of such polymers differ from those inherent in analogues of low molecular weight or in mechanical mixtures of the latter compounds with polymers. The difference in behaviour is explained by the steric and polar influence of the macromolecule on the initial and the photoinduced forms of the photochromic compound. A list of 55 references is included.